This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. As with previous proposals the concept remains to develop and test a wave propagation model that simulates the bone-conducted sound through the human skull. A highly efficient prototype 3D program has been developed, benchmarked against known solutions and partially used to simulate a head sensitivity mapping done by the Army Research Lab. An MRAC has been submitted in order to complete the sensitivity mapping simulate more complex systems such as the those with different types of hearing protection and continue to develop the algorithm to account for different physical phenomena such as attenuation and shear effects. A DAC renewal account is requested in order to use Maverick's visualization software such that some of the existing simulation data can be displayed. The PI intends to prepare a submission to the Teragrid 08 conference and therefore desires a quick turnaround for a 30000 DAC request in order to fulfill this intention.